Glycol ethers have solvent properties of both alcohols and ethers and are thus very valuable and widely used as industrial solvents. However, the smaller members of this group have recently been incriminated as having selected toxicity to the reproductive system. This fact has increased the use of the already widely used ethylene glycol monobutyl ether (2-butoxyethanol; BE) so that current use of this compound approaches one quarter billion pounds per year. Despite its wide use this chemical has been the subject of relatively little study to characterize its acute or chronic toxicity. The present investigations of the fate of BE in higher animals have determined that it is readily absorbed from the gastrointestinal tract and rapidly metabolized to butoxyacetic acid (BAA), BE-glucuronide and BE-sulfate as well as CO2. Additional work don on this project has demonstrated that, in the rat, BE administration causes severe acute hemolytic anemia as evidenced by a drastic decrease in red blood cells, hemoglobin and hematocrit. Further, this work has demonstrated that sensitivity to the toxicity of BE is age dependent becoming increasingly severe with increasing age. Work has also demonstrated that BE induced anemia can be prevented by prior administration of inhibitors of alcohol dehydrogenase such as pyrazole. This and additional findings indicate that BE metabolism via alcohol and aldehyde dehydrogenase is a prerequisite for hemototoxicity. The ultimate metabolite BAA is believed to account for BE toxicity and studies of BAA In vitro have demonstrated that incubation of BAA with whole blood results in a dramatic increase in hematocrit due to red blood cell swelling followed by hemolysis. Work continues on the characterization of BE toxicity and its relevance to human health.